/* ----------------------------------------------------------------------
* Copyright (c) Colorado School of Mines, 1996.
All rights reserved.
segy.h - include file for SEGY traces
*
* declarations for:
* typedef struct {} segy - the trace identification header
* typedef struct {} bhed - binary header
*
* Note:
* If header words are added, run the makefile in this directory
* to recreate hdr.h.
*
* Reference:
* K. M. Barry, D. A. Cavers and C. W. Kneale, "Special Report:
* Recommended Standards for Digital Tape Formats",
* Geophysics, vol. 40, no. 2 (April 1975), P. 344-352.
*
----------------------------------------------------------------------*/
#ifndef SEGY_H
#define SEGY_H
#define SU_NFLTS 32768 /* Arbitrary limit on data array size */
/* TYPEDEFS */
#ifdef _CRAY
typedef struct { /* segy - trace identification header */
signed tracl :32; /* trace sequence number within line */
signed tracr :32; /* trace sequence number within reel */
signed fldr :32; /* field record number */
signed tracf :32; /* trace number within field record */
signed ep :32; /* energy source point number */
signed cdp :32; /* CDP ensemble number */
signed cdpt :32; /* trace number within CDP ensemble */
signed trid :16; /* trace identification code:
1 = seismic data
2 = dead
3 = dummy
4 = time break
5 = uphole
6 = sweep
7 = timing
8 = water break
9---, N = optional use (N = 32,767)
Following are CWP id flags:
9 = autocorrelation
10 = Fourier transformed - no packing
xr[0],xi[0], ..., xr[N-1],xi[N-1]
11 = Fourier transformed - unpacked Nyquist
xr[0],xi[0],...,xr[N/2],xi[N/2]
12 = Fourier transformed - packed Nyquist
even N:
xr[0],xr[N/2],xr[1],xi[1], ...,
xr[N/2 -1],xi[N/2 -1]
(note the exceptional second entry)
odd N:
xr[0],xr[(N-1)/2],xr[1],xi[1], ...,
xr[(N-1)/2 -1],xi[(N-1)/2 -1],xi[(N-1)/2]
(note the exceptional second & last entries)
13 = Complex signal in the time domain
xr[0],xi[0], ..., xr[N-1],xi[N-1]
14 = Fourier transformed - amplitude/phase
a[0],p[0], ..., a[N-1],p[N-1]
15 = Complex time signal - amplitude/phase
a[0],p[0], ..., a[N-1],p[N-1]
16 = Real part of complex trace from 0 to Nyquist
17 = Imag part of complex trace from 0 to Nyquist
18 = Amplitude of complex trace from 0 to Nyquist
19 = Phase of complex trace from 0 to Nyquist
21 = Wavenumber time domain (k-t)
22 = Wavenumber frequency (k-omega)
23 = Envelope of the complex time trace
24 = Phase of the complex time trace
25 = Frequency of the complex time trace
30 = Depth-Range (z-x) traces
101 = Seismic data packed to bytes (by supack1)
102 = Seismic data packed to 2 bytes (by supack2)
*/
signed nvs :16; /* number of vertically summed traces (see vscode
in bhed structure) */
signed nhs :16; /* number of horizontally summed traces (see vscode
in bhed structure) */
signed duse :16; /* data use:
1 = production
2 = test */
signed offset :32; /* distance from source point to receiver
group (negative if opposite to direction
in which the line was shot) */
signed gelev :32; /* receiver group elevation from sea level
(above sea level is positive) */
signed selev :32; /* source elevation from sea level
(above sea level is positive) */
signed sdepth :32; /* source depth (positive) */
signed gdel :32; /* datum elevation at receiver group */
signed sdel :32; /* datum elevation at source */
signed swdep :32; /* water depth at source */
signed gwdep :32; /* water depth at receiver group */
signed scalel :16; /* scale factor for previous 7 entries
with value plus or minus 10 to the
power 0, 1, 2, 3, or 4 (if positive,
multiply, if negative divide) */
signed scalco :16; /* scale factor for next 4 entries
with value plus or minus 10 to the
power 0, 1, 2, 3, or 4 (if positive,
multiply, if negative divide) */
signed sx :32; /* X source coordinate */
signed sy :32; /* Y source coordinate */
signed gx :32; /* X group coordinate */
signed gy :32; /* Y group coordinate */
signed counit :16; /* coordinate units code:
for previous four entries
1 = length (meters or feet)
2 = seconds of arc (in this case, the
X values are longitude and the Y values
are latitude, a positive value designates
the number of seconds east of Greenwich
or north of the equator */
signed wevel :16; /* weathering velocity */
signed swevel :16; /* subweathering velocity */
signed sut :16; /* uphole time at source */
signed gut :16; /* uphole time at receiver group */
signed sstat :16; /* source static correction */
signed gstat :16; /* group static correction */
signed tstat :16; /* total static applied */
signed laga :16; /* lag time A, time in ms between end of 240-
byte trace identification header and time
break, positive if time break occurs after
end of header, time break is defined as
the initiation pulse which maybe recorded
on an auxiliary trace or as otherwise
specified by the recording system */
signed lagb :16; /* lag time B, time in ms between the time break
and the initiation time of the energy source,
may be positive or negative */
signed delrt :16; /* delay recording time, time in ms between
initiation time of energy source and time
when recording of data samples begins
(for deep water work if recording does not
start at zero time) */
signed muts :16; /* mute time--start */
signed mute :16; /* mute time--end */
unsigned ns :16; /* number of samples in this trace */
unsigned dt :16; /* sample interval; in micro-seconds */
signed gain :16; /* gain type of field instruments code:
1 = fixed
2 = binary
3 = floating point
4 ---- N = optional use */
signed igc :16; /* instrument gain constant */
signed igi :16; /* instrument early or initial gain */
signed corr :16; /* correlated:
1 = no
2 = yes */
signed sfs :16; /* sweep frequency at start */
signed sfe :16; /* sweep frequency at end */
signed slen :16; /* sweep length in ms */
signed styp :16; /* sweep type code:
1 = linear
2 = cos-squared
3 = other */
signed stas :16; /* sweep trace length at start in ms */
signed stae :16; /* sweep trace length at end in ms */
signed tatyp :16; /* taper type: 1=linear, 2=cos^2, 3=other */
signed afilf :16; /* alias filter frequency if used */
signed afils :16; /* alias filter slope */
signed nofilf :16; /* notch filter frequency if used */
signed nofils :16; /* notch filter slope */
signed lcf :16; /* low cut frequency if used */
signed hcf :16; /* high cut frequncy if used */
signed lcs :16; /* low cut slope */
signed hcs :16; /* high cut slope */
signed year :16; /* year data recorded */
signed day :16; /* day of year */
signed hour :16; /* hour of day (24 hour clock) */
signed minute :16; /* minute of hour */
signed sec :16; /* second of minute */
signed timbas :16; /* time basis code:
1 = local
2 = GMT
3 = other */
signed trwf :16; /* trace weighting factor, defined as 1/2^N
volts for the least sigificant bit */
signed grnors :16; /* geophone group number of roll switch
position one */
signed grnofr :16; /* geophone group number of trace one within
original field record */
signed grnlof :16; /* geophone group number of last trace within
original field record */
signed gaps :16; /* gap size (total number of groups dropped) */
signed otrav :16; /* overtravel taper code:
1 = down (or behind)
2 = up (or ahead) */
/* local assignments */
/*signed pad :32; */ /* double word alignment for Cray 64-bit floats */
float d1; /* sample spacing for non-seismic data */
float f1; /* first sample location for non-seismic data */
float d2; /* sample spacing between traces */
float f2; /* first trace location */
float ungpow; /* negative of power used for dynamic
range compression */
float unscale; /* reciprocal of scaling factor to normalize
range */
signed ntr :32; /* number of traces */
signed mark :16; /* mark selected traces */
signed unass :16; /* unassigned values */
float data[SU_NFLTS];
} segy;
typedef struct { /* bhed - binary header */
int jobid :32; /* job identification number */
int lino :32; /* line number (only one line per reel) */
int reno :32; /* reel number */
short ntrpr :16; /* number of data traces per record */
short nart :16; /* number of auxiliary traces per record */
short hdt :16; /* sample interval in micro secs for this reel */
short dto :16; /* same for original field recording */
short hns :16; /* number of samples per trace for this reel */
short nso :16; /* same for original field recording */
short format :16; /* data sample format code:
1 = floating point (4 bytes)
2 = fixed point (4 bytes)
3 = fixed point (2 bytes)
4 = fixed point w/gain code (4 bytes) */
short fold :16; /* CDP fold expected per CDP ensemble */
short tsort :16; /* trace sorting code:
1 = as recorded (no sorting)
2 = CDP ensemble
3 = single fold continuous profile
4 = horizontally stacked */
short vscode :16; /* vertical sum code:
1 = no sum
2 = two sum ...
N = N sum (N = 32,767) */
short hsfs :16; /* sweep frequency at start */
short hsfe :16; /* sweep frequency at end */
short hslen :16; /* sweep length (ms) */
short hstyp :16; /* sweep type code:
1 = linear
2 = parabolic
3 = exponential
4 = other */
short schn :16; /* trace number of sweep channel */
short hstas :16; /* sweep trace taper length at start if
tapered (the taper starts at zero time
and is effective for this length) */
short hstae :16; /* sweep trace taper length at end (the ending
taper starts at sweep length minus the taper
length at end) */
short htatyp :16; /* sweep trace taper type code:
1 = linear
2 = cos-squared
3 = other */
short hcorr :16; /* correlated data traces code:
1 = no
2 = yes */
short bgrcv :16; /* binary gain recovered code:
1 = yes
2 = no */
short rcvm :16; /* amplitude recovery method code:
1 = none
2 = spherical divergence
3 = AGC
4 = other */
short mfeet :16; /* measurement system code:
1 = meters
2 = feet */
short polyt :16; /* impulse signal polarity code:
1 = increase in pressure or upward
geophone case movement gives
negative number on tape
2 = increase in pressure or upward
geophone case movement gives
positive number on tape */
short vpol :16; /* vibratory polarity code:
code seismic signal lags pilot by
1 337.5 to 22.5 degrees
2 22.5 to 67.5 degrees
3 67.5 to 112.5 degrees
4 112.5 to 157.5 degrees
5 157.5 to 202.5 degrees
6 202.5 to 247.5 degrees
7 247.5 to 292.5 degrees
8 293.5 to 337.5 degrees */
signed pad :32; /* double word alignment pad */
double hunass[21]; /* unassigned, double is portable! */
} bhed;
#else /* bit fields may not be portable! */
typedef struct { /* segy - trace identification header */
int tracl ; /* trace sequence number within line */
int tracr ; /* trace sequence number within reel */
int fldr ; /* field record number */
int tracf ; /* trace number within field record */
int ep ; /* energy source point number */
int cdp ; /* CDP ensemble number */
int cdpt ; /* trace number within CDP ensemble */
short trid ; /* trace identification code:
1 = seismic data
2 = dead
3 = dummy
4 = time break
5 = uphole
6 = sweep
7 = timing
8 = water break
9---, N = optional use (N = 32,767)
Following are CWP id flags:
9 = autocorrelation
10 = Fourier transformed - no packing
xr[0],xi[0], ..., xr[N-1],xi[N-1]
11 = Fourier transformed - unpacked Nyquist
xr[0],xi[0],...,xr[N/2],xi[N/2]
12 = Fourier transformed - packed Nyquist
even N:
xr[0],xr[N/2],xr[1],xi[1], ...,
xr[N/2 -1],xi[N/2 -1]
(note the exceptional second entry)
odd N:
xr[0],xr[(N-1)/2],xr[1],xi[1], ...,
xr[(N-1)/2 -1],xi[(N-1)/2 -1],xi[(N-1)/2]
(note the exceptional second & last entries)
13 = Complex signal in the time domain
xr[0],xi[0], ..., xr[N-1],xi[N-1]
14 = Fourier transformed - amplitude/phase
a[0],p[0], ..., a[N-1],p[N-1]
15 = Complex time signal - amplitude/phase
a[0],p[0], ..., a[N-1],p[N-1]
16 = Real part of complex trace from 0 to Nyquist
17 = Imag part of complex trace from 0 to Nyquist
18 = Amplitude of complex trace from 0 to Nyquist
19 = Phase of complex trace from 0 to Nyquist
21 = Wavenumber time domain (k-t)
22 = Wavenumber frequency (k-omega)
23 = Envelope of the complex time trace
24 = Phase of the complex time trace
25 = Frequency of the complex time trace
30 = Depth-Range (z-x) traces
101 = Seismic data packed to bytes (by supack1)
102 = Seismic data packed to 2 bytes (by supack2)
*/
short nvs ; /* number of vertically summed traces (see vscode
in bhed structure) */
short nhs ; /* number of horizontally summed traces (see vscode
in bhed structure) */
short duse ; /* data use:
1 = production
2 = test */
int offset ; /* distance from source point to receiver
group (negative if opposite to direction
in which the line was shot) */
int gelev ; /* receiver group elevation from sea level
(above sea level is positive) */
int selev ; /* source elevation from sea level
(above sea level is positive) */
int sdepth ; /* source depth (positive) */
int gdel ; /* datum elevation at receiver group */
int sdel ; /* datum elevation at source */
int swdep ; /* water depth at source */
int gwdep ; /* water depth at receiver group */
short scalel ; /* scale factor for previous 7 entries
with value plus or minus 10 to the
power 0, 1, 2, 3, or 4 (if positive,
multiply, if negative divide) */
short scalco ; /* scale factor for next 4 entries
with value plus or minus 10 to the
power 0, 1, 2, 3, or 4 (if positive,
multiply, if negative divide) */
int sx ; /* X source coordinate */
int sy ; /* Y source coordinate */
int gx ; /* X group coordinate */
int gy ; /* Y group coordinate */
short counit ; /* coordinate units code:
for previous four entries
1 = length (meters or feet)
2 = seconds of arc (in this case, the
X values are longitude and the Y values
are latitude, a positive value designates
the number of seconds east of Greenwich
or north of the equator */
short wevel ; /* weathering velocity */
short swevel ; /* subweathering velocity */
short sut ; /* uphole time at source */
short gut ; /* uphole time at receiver group */
short sstat ; /* source static correction */
short gstat ; /* group static correction */
short tstat ; /* total static applied */
short laga ; /* lag time A, time in ms between end of 240-
byte trace identification header and time
break, positive if time break occurs after
end of header, time break is defined as
the initiation pulse which maybe recorded
on an auxiliary trace or as otherwise
specified by the recording system */
short lagb ; /* lag time B, time in ms between the time break
and the initiation time of the energy source,
may be positive or negative */
short delrt ; /* delay recording time, time in ms between
initiation time of energy source and time
when recording of data samples begins
(for deep water work if recording does not
start at zero time) */
short muts ; /* mute time--start */
short mute ; /* mute time--end */
unsigned short ns ; /* number of samples in this trace */
unsigned short dt ; /* sample interval; in micro-seconds */
short gain ; /* gain type of field instruments code:
1 = fixed
2 = binary
3 = floating point
4 ---- N = optional use */
short igc ; /* instrument gain constant */
short igi ; /* instrument early or initial gain */
short corr ; /* correlated:
1 = no
2 = yes */
short sfs ; /* sweep frequency at start */
short sfe ; /* sweep frequency at end */
short slen ; /* sweep length in ms */
short styp ; /* sweep type code:
1 = linear
2 = cos-squared
3 = other */
short stas ; /* sweep trace length at start in ms */
short stae ; /* sweep trace length at end in ms */
short tatyp ; /* taper type: 1=linear, 2=cos^2, 3=other */
short afilf ; /* alias filter frequency if used */
short afils ; /* alias filter slope */
short nofilf ; /* notch filter frequency if used */
short nofils ; /* notch filter slope */
short lcf ; /* low cut frequency if used */
short hcf ; /* high cut frequncy if used */
short lcs ; /* low cut slope */
short hcs ; /* high cut slope */
short year ; /* year data recorded */
short day ; /* day of year */
short hour ; /* hour of day (24 hour clock) */
short minute ; /* minute of hour */
short sec ; /* second of minute */
short timbas ; /* time basis code:
1 = local
2 = GMT
3 = other */
short trwf ; /* trace weighting factor, defined as 1/2^N
volts for the least sigificant bit */
short grnors ; /* geophone group number of roll switch
position one */
short grnofr ; /* geophone group number of trace one within
original field record */
short grnlof ; /* geophone group number of last trace within
original field record */
short gaps ; /* gap size (total number of groups dropped) */
short otrav ; /* overtravel taper code:
1 = down (or behind)
2 = up (or ahead) */
/* local assignments */
float d1; /* sample spacing for non-seismic data */
float f1; /* first sample location for non-seismic data */
float d2; /* sample spacing between traces */
float f2; /* first trace location */
float ungpow; /* negative of power used for dynamic
range compression */
float unscale; /* reciprocal of scaling factor to normalize
range */
int ntr ; /* number of traces */
short mark ; /* mark selected traces */
short unass[15]; /* unassigned values */
float data[SU_NFLTS];
} segy;
typedef struct { /* bhed - binary header */
int jobid ; /* job identification number */
int lino ; /* line number (only one line per reel) */
int reno ; /* reel number */
short ntrpr ; /* number of data traces per record */
short nart ; /* number of auxiliary traces per record */
short hdt ; /* sample interval in micro secs for this reel */
short dto ; /* same for original field recording */
short hns ; /* number of samples per trace for this reel */
short nso ; /* same for original field recording */
short format ; /* data sample format code:
1 = floating point (4 bytes)
2 = fixed point (4 bytes)
3 = fixed point (2 bytes)
4 = fixed point w/gain code (4 bytes) */
short fold ; /* CDP fold expected per CDP ensemble */
short tsort ; /* trace sorting code:
1 = as recorded (no sorting)
2 = CDP ensemble
3 = single fold continuous profile
4 = horizontally stacked */
short vscode ; /* vertical sum code:
1 = no sum
2 = two sum ...
N = N sum (N = 32,767) */
short hsfs ; /* sweep frequency at start */
short hsfe ; /* sweep frequency at end */
short hslen ; /* sweep length (ms) */
short hstyp ; /* sweep type code:
1 = linear
2 = parabolic
3 = exponential
4 = other */
short schn ; /* trace number of sweep channel */
short hstas ; /* sweep trace taper length at start if
tapered (the taper starts at zero time
and is effective for this length) */
short hstae ; /* sweep trace taper length at end (the ending
taper starts at sweep length minus the taper
length at end) */
short htatyp ; /* sweep trace taper type code:
1 = linear
2 = cos-squared
3 = other */
short hcorr ; /* correlated data traces code:
1 = no
2 = yes */
short bgrcv ; /* binary gain recovered code:
1 = yes
2 = no */
short rcvm ; /* amplitude recovery method code:
1 = none
2 = spherical divergence
3 = AGC
4 = other */
short mfeet ; /* measurement system code:
1 = meters
2 = feet */
short polyt ; /* impulse signal polarity code:
1 = increase in pressure or upward
geophone case movement gives
negative number on tape
2 = increase in pressure or upward
geophone case movement gives
positive number on tape */
short vpol ; /* vibratory polarity code:
code seismic signal lags pilot by
1 337.5 to 22.5 degrees
2 22.5 to 67.5 degrees
3 67.5 to 112.5 degrees
4 112.5 to 157.5 degrees
5 157.5 to 202.5 degrees
6 202.5 to 247.5 degrees
7 247.5 to 292.5 degrees
8 293.5 to 337.5 degrees */
char pad[4] ; /* double word alignment pad */
int hunass[42]; /* unassigned */
} bhed;
#endif /* end of ifdef CRAY, the bit fields are not portable */
/* DEFINES */
#define gettr(x) fgettr(stdin, (x))
#define vgettr(x) fvgettr(stdin, (x))
#define puttr(x) fputtr(stdout, (x))
#define gettra(x, y) fgettra(stdin, (x), (y))
/* The following refer to the trid field in segy.h */
/* CHARPACK represents byte packed seismic data from supack1 */
#define CHARPACK 101
/* SHORTPACK represents 2 byte packed seismic data from supack2 */
#define SHORTPACK 102
/* TREAL represents real time traces */
#define TREAL 1
/* TDEAD represents dead time traces */
#define TDEAD 2
/* TDUMMY represents dummy time traces */
#define TDUMMY 3
/* TBREAK represents time break traces */
#define TBREAK 4
/* UPHOLE represents uphole traces */
#define UPHOLE 5
/* SWEEP represents sweep traces */
#define SWEEP 6
/* TIMING represents timing traces */
#define TIMING 7
/* WBREAK represents timing traces */
#define WBREAK 8
/* TCMPLX represents complex time traces */
#define TCMPLX 13
/* TAMPH represents time domain data in amplitude/phase form */
#define TAMPH 15
/* FPACK represents packed frequency domain data */
#define FPACK 12
/* FUNPACKNYQ represents complex frequency domain data */
#define FUNPACKNYQ 11
/* FCMPLX represents complex frequency domain data */
#define FCMPLX 10
/* FAMPH represents freq domain data in amplitude/phase form */
#define FAMPH 14
/* REALPART represents the real part of a trace to Nyquist */
#define REALPART 16
/* IMAGPART represents the imaginary part of a trace to Nyquist */
#define IMAGPART 17
/* AMPLITUDE represents the amplitude of a trace to Nyquist */
#define AMPLITUDE 18
/* PHASE represents the phase of a trace to Nyquist */
#define PHASE 19
/* KT represents wavenumber-time domain data */
#define KT 21
/* KOMEGA represents wavenumber-frequency domain data */
#define KOMEGA 22
/* ENVELOPE represents the envelope of the complex time trace */
#define ENVELOPE 23
/* INSTPHASE represents the phase of the complex time trace */
#define INSTPHASE 24
/* INSTFREQ represents the frequency of the complex time trace */
#define INSTFREQ 25
/* DEPTH represents traces in depth-range (z-x) */
#define TRID_DEPTH 30
#define ISSEISMIC(id) ( (id)==0 || (id)==TREAL || (id)==TDEAD || (id)==TDUMMY )
/* FUNCTION PROTOTYPES */
#ifdef __cplusplus /* if C++, specify external linkage to C functions */
extern "C" {
#endif
int fgettr(FILE *fp, segy *tp);
int fvgettr(FILE *fp, segy *tp);
void fputtr(FILE *fp, segy *tp);
int fgettra(FILE *fp, segy *tp, int itr);
/* hdrpkge */
/* void gethval(const segy *tp, int index, Value *valp);
void puthval(segy *tp, int index, Value *valp);
void getbhval(const bhed *bhp, int index, Value *valp);
void putbhval(bhed *bhp, int index, Value *valp);
void gethdval(const segy *tp, char *key, Value *valp);
void puthdval(segy *tp, char *key, Value *valp);
char *hdtype(const char *key);
char *getkey(const int index);
int getindex(const char *key);
void swaphval(segy *tp, int index);
void swapbhval(bhed *bhp, int index);
void printheader(const segy *tp); */
void tabplot(segy *tp, int itmin, int itmax);
#ifdef __cplusplus /* if C++, end external linkage specification */
}
#endif
#endif